On Thu, May 11, 2017 at 4:55 PM, Bernd Oppolzer <[email protected]>
wrote:
> Yes, of course. I detected the error when I looked at
> my piece of software from last year which examined the different LE heaps.
>
> and: thank you, Allan Kielstra, for the clarification regarding Reg 12;
> so my call to the ASSEMBLER function to get the address of the CEECAA will
> work?
>
> Here is the ASSEMBLER program which returns the registers (especially reg
> 12)
> to the C program:
>
> MDV9970 CSECT
> MDV9970 AMODE 31
> MDV9970 RMODE ANY
> *
> ***************************************************************
> * UNTERPROGRAMM ZUR ERMITTLUNG DER
> * AKTUELLEN REGISTERSTAENDE UND ABLAGE
> * IN EINEN C-BUFFER (DER ALS PARAMETER
> * UEBERGEBEN WIRD). ZWECK DER UEBUNG:
> * ZUGRIFF AUF CEECAA (COMMON ANCHOR AREA VOM LE)
> * UND DAMIT AUF ANYHEAP UND BELOWHEAP
> * BERND OPPOLZER / AUGUST 2016
> ***************************************************************
> *
> R0 EQU 0
> R1 EQU 1
> R2 EQU 2
> R3 EQU 3
> R4 EQU 4
> R5 EQU 5
> R6 EQU 6
> R7 EQU 7
> R8 EQU 8
> R9 EQU 9
> RA EQU 10
> RB EQU 11
> RC EQU 12
> RD EQU 13
> RE EQU 14
> RF EQU 15
> *
> STM RE,RC,12(RD) REGISTER SICHERN
> USING MDV9970,RF ADRESSIERUNG HERSTELLEN
> L R3,0(R1) ADRESSE VOM BUFFER = 1. PARAMETER
> MVC 0(52,R3),20(RD) REGISTER 0 BIS 12 AUS SA UEBERTR.
> ST RD,52(R3) REGISTER 13 ABSPEICHERN
> MVC 56(8,R3),12(RD) REGISTER 14 UND 15 AUS SA UEBERTR.
> LM RE,RC,12(RD) REGISTER ZURUECKLADEN
> BR RE UND RUECKSPRUNG
> *
> END MDV9970
>
Looks fairly good to me. For returning the 32 bit registers, that is. But
it seems to be "overkill" to me. The "guts" of the routine could be just:
STM R0,RF,12(RD) SAVE ALL REGS.
L R3,0(,R1) POINT TO RETURN AREA
MVC 0(64,R3),12(RD) MOVE REGS AT ENTRY
SLR RF,RF
BR RE
This does not use standard linkage, but is that really necessary? The only
possible abend would be on the MVC, if the routine is not called properly.
I included the SLR just to "zero" the return code. If the C code is
declared as returning "void" (e.g. "void MDV9970(regs) ;" where regs is
defined as "uint regs[16];" ) then R15 on exit is ignored.
>
> Kind regards
>
> Bernd
>
>
>
--
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selling goods, particularly if the goods are worthless. -- Sinclair Lewis
Maranatha! <><
John McKown
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